Fionn blinked a couple times before he managed to actually respond to O'Connor - he was insulted, and confused for the couple of seconds it took for him figure out what must have happened. "How stupid do you think I am? If I was the sort who spied on his own team, don't you think the last thing I'd do is tip off the paranoid homicidal psychopath and the mesh-phobic probable-killer? I had a fucking guess about what you might be thinking, and didn't want you to do something stupid - is it my fault you're an easier read than a children's book? Hell, I had you pegged before we even met Coyote, jackass."
[spoiler]At three hits, Clem probably notices Fionn's confusion, and the fact that he's more insulted by the accusation than anything. He doesn't appear to be hiding anything.[/spoiler]